HEIDENHAIN TNC 150 B Mounting Instructions page 51

8.1 .l Buffer battery swich-off
Open the outer and inner cover to batteries; this will switch off buffer batteries. Before replacing covers, wait a
few minutes so that any previously programmed,incompatible machine parameters are erased.
8.1.2 Axis designation for NC-machines and "right-hand-rule"
The three main axes are defined by NC-standards. Traversitq directions can be determined by the "right hand
rule". In addition, the traversing direction of the tool-axis tcwards the workpiece corresponds to the negative
traversing direct&t.
Example:
Universal
machine
+ Z direction
middle finger
"Right hand rule"
Coordinates are correlated
to the fingers.
When programming,only tool movement is considered (relative movement of tool) i.e. whilst programming the
operator always assumes that the tool is moving.
Tool movement + X
c
-Table movement + X'
Wil:h the universal milling machine as illustrated above,
the milling tool should, for example, traverse in a
positive direction. However, due to the table moving
in i:his axis and not the tool, the table must move in
th6' left-hand direction. The relative movement of the
tool is therefore in the right-hand direction, i.e. in the
positive X direction. In this case, the traversing
dirl?ction of the table is designated X'.
The machine tool manufacturer decides whether the fourth 3xis is to be used for a rotary table or as an
additional linear axis and also which designation this axis will receive on the display screen:
+X
Rotary axis
I 'ourth linear axis
The rotary axis is designated with the letters A, B
If the fourth axis is to be used as a linear axis, the
or C; the correlation to the main axes and the
designation of this axis is U, V or W.
rotating direction is shown in the above illustration.
The correlation to the main axes is shown above.